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The present research investigates the corrosion behavior of aluminum metal matrix composites (AMMCs) in NaCl solution. The test was designed and performed based on Taguchi’s L8 orthogonal array. The stir casting technique fabricates the AMMCs, and silicon carbide (SiC) is individually reinforced in Al 6061 and Al 5052 matrix. The SiC particle are reinforced in a matrix with 5% and 10% separately in Al 6061 and Al 5052. The test variables used during corrosion studies were reinforced Al matrix, wt% of SiC, molar solution, and corrosion duration for stir-casted composite samples. The Al 6061 and Al 5052 composites were tested in 1M and 2M molar NaCl solutions for 15 and 30 days exposure duration. According to ASTM G31, the solution immersion tests were carried out. The corrosion surfaces are examined by optical microscope and field emission scanning electron microscopy (FESEM) equipment. Through microstructure, it is noted that the corrosion concentration is along the grain boundaries.

This study reports a simulation model to predict the coating thickness during the Electric Discharge Coating (EDC) process and validates it with experimental analysis. Solid lubricant coating was developed on the mild steel substrate using WS2, and Cu (50:50) based green compact electrodes. The simulation model developed by using COMSOL Multiphysics (5.5) software and the accumulated growth height from the heavy species transport calculated as coating thickness. Experiments with the same input parameters and coating thickness were measured, compared with simulation result and the results show with error fraction of 3% to 12%. Therefore, the present developed simulation model can be employed to predict the thickness of solid lubricant coating by EDC process with minimum error.

The research aims to optimize the surface roughness, material removal rate (MRR), tool wear, and spark gap for input machining parameters such as Pulse on-off time and wire feed rate. The experiment results of WEDM of Duplex stainless steel are optimized by ANOVA and Response surface methodology (RSM) approach. Taguchi’s orthogonal array L9 (3*3) was used to design the test condition for the experiment. After the model validation, ANOVA was used to identify the most significant input factor on the output. Response surface methodology was used to find the ideal cutting conditions which produce the best-desired output in terms of less tool wear, lower surface roughness, lower spark gap, and higher material removal rate. The optimal MRR, Spark Gap, surface roughness, and tool wear parameters for Duplex Stainless Steel are obtained at Pulse on 110.23, Pulse off time of 56.0, and a wire feed rate of 1.0.

Inconel 617 is found in industrial sectors, including chemical, petrochemical, and nuclear. This work mainly concentrates on the analysis and the input-parameters optimization that minimizes the surface roughness, tool wear, and force in turning Inconel 617. Then, the chip and inserts are morphologically characterized using optical images. The residual plots showed that the accomplished investigational data are reliable and suitable for further study. Abrasion is accountable for tool wear mechanisms, and a rise in cutting speed affects the tool wear profile. Chip burr adhering to the flank surface is responsible for the surface roughness increase. Optimum cutting parameters are determined as 0.3mm depth of cut, 0.1mm/rev feed rate, and 220m/min cutting speed. Feed rate is the most influential parameter for process variables through Criteria Importance through Inter Criteria and weighted aggregated sum product assessment methodology.

The utilization of Additive Manufacturing (AM) technology in the current manufacturing sector is growing day - by - day. This is made possible by the constant development of new materials and techniques to overcome the difficulties that are encountered while fabricating a part. In AM, parts are fabricated by laying successive layers on one another till the complete part is build. This gives AM an edge over conventional manufacturing. Even intricate or hollow parts can be fabricated with the same ease as fabricating a solid part. The key objective of this project is to evaluate and compare mechanical properties of Polyethylene Terephthalate - Glycol modified (PETG) and Carbon fiber reinforced Polyethylene Terephthalate - Glycol modified (CF - PETG), which are fabricated using Fused Deposition Modelling (FDM) process of AM. The ASTM standards D638 and D790 were followed for fabricating tensile test and Flexural test specimens respectively.

The developed model analysis is built in matrix runs to optimise the friction stir welding parameters of rotational speed, welding speed, shoulder diameter and tilt angle in this research. The aim of any design is to maximise the welded properties, either to surpass the base metal properties. The model that is created is the product of a number of regression methods that have been tested for adequacy. In this model we have taken three levels of varying parameters shoulder diameters, rotational speed, welding speed. Mathematical model is developed for the effect of three process parameter at three levels using response surface methodology (RSM).

Aluminium metal matrix composite are broadly used in various field like aerospace, marine and automobile application. The application of composites necessitates joining process and its difficult due to different materials. To address the considering difficulties the present study is, Cr2O3 was reinforced in Al 6061 matrix in 2 % to 6 % in the incremental step of 2 %. The stir casting method was used to fabricate the composites with 300 rpm stirring speed and the stirring time duration was 3 min throughout the fabrication process. The H13 tool is used for prepared friction stir welded (FSW) joints and tool having 6.7 mm pin diameter and 6 mm pin height. The fabrication process is conducted by 500 rpm and 700 rpm tool rotational speed with 50 mm/min and 60 mm/min welding speed receptively. The atmospheric environmental condition was preferred to perform friction stir welding.

Fiber-reinforced polymer composites propose exceptional directional mechanical properties, and combining their advantages with the potential of 3D printing has resulted in many novel research fronts. Industries have started using 3D printed components which are rapidly replacing conventional material components in most of the industries. Carbon fiber reinforced Polylactic Acid (PLA) often finds its application in reasonably high loading conditions working at lesser speed like lightweight gears, spanners, nuts, and bolts. Wear reduction is an important factor that plays an important role in prolonging the component's life. Hence, it is crucial to optimize 3D printing parameters to get desired strength according to the application. The aim of this paper is to conduct the wear rate test on the Fused Deposition Modelled (FDM) printed carbon fiber reinforced PLA parts, to identify the optimum printing parameters which are crucial for wear reduction.

Dissimilar metal welds (DMWs), between austenitic stainless steel (ASS) and micro alloyed high strength low alloy steel (HSLA), are used in high temperature applications in power stations and petrochemical plants. The gas metal arc welding (GMAW) has surpassed the shielded metal arc welding (SMAW) process due to its advantages of producing fast, long, clean continuous weld at any position [1, 2, 3, 4, 5]. A studies on mechanical and metallurgical properties of conventional V-groove SMAW and GMA Welding of dissimilar 20 mm thick 304LN ASS and micro alloyed HSLA steel plate were carried out by using austenitic E308L- 15 electrode with gas tungsten arc welding (GTAW) root pass. The tensile (axial and all-weld) properties, hardness and microstructure of the weld and HAZ are analyzed.

The objective of the study is to investigate the effect of current pulsation frequency on the weld bead microstructure, segregation and hardness of Hastelloy C-2000 weldments. Bead on Plate (BoP) welds were made by using Pulsed Current Gas Tungsten Arc Welding method (PCGTAW) at eleven different frequencies. The weld bead width and depth of penetration was measured with the help of Dinolite macro analyzer. The microstructure of weldments are further examined through optical microscope and Scanning Electron Microscopy (SEM) to identify the type of grain, grain coarsening and extent of the Heat Affected Zone (HAZ). The grain structure turn into finer and equiaxed in all cases and there was an optimum frequency range over which the significant grain refinement was observed. Microsegregation of alloying elements were computed with the aid of Energy Dispersive X-ray Spectroscopy (EDS). Vickers Hardness Tester was used to measure the hardness of the weld samples at ambient conditions.

This study examines the influence of cryogenic treatment on the microstructure and on the physical properties of the rapid prototype SLS material. The wear properties of the rapid prototype SLS material both before and after cryogenic treatment are studied in three phases. Phase I deals with the sample preparation through the SLS technique; Phase II involves the preliminary tests like roughness test, hardness test, SEM and wear test. Phase III is the cryogenic treatment of the sample in the setup designed. The cryogenic coolant used is Nitrogen, having a boiling point of 77 K, and the whole treatment process takes about 2 to 3 days. Phase IV deals with the testing of the cryogenically treated samples in which similar tests to that in Phase I are carried out. These results are tabulated and graphs are plotted. Furthermore, the percentage change in the hardness and wear properties of the samples are found.

Duplex stainless steel (DSS) 2205 grade is welded with austenitic filler wires (ERNiCrMo-3 and ERNiCrMo-4) using gas tungsten arc welding (GTAW) process to operate at marine environments. Microstructure using optical (OM) and scanning electron microscopes (SEM) with energy dispersive spectroscope (EDS) are utilized to examine the metallurgical characterization of DSS 2205 weldments. Microhardness, impact, and tensile tests are employed to obtain the mechanical properties of weldments. Secondary precipitates such as Mo23C6 and Cr23C6 are formed in the ERNiCrMo-3 weldment which reduced the mechanical properties. In this study, ERNiCrMo-4 filler wire is provided enhanced mechanical properties for welding DSS 2205.